I used DHCP at first but had issues with that, which I address to config part of Volumio.
See Networking is a mess
So I use static now, and that has other issues (see link above).
But with that I can at least access the webpage just fine from the laptop and desktop.
There is nothing using that IP address in my network.
Everything separated in IP blocks. I use 10.42.0.0/16 at home and computers like my desktop, laptop and things like my CoreELEC and this Volumio VIM3L’s are in the 10.42.60.x range.
Even when using DHCP the Volumio has it’s address fixed to that since I use the DNS record to read the IP address. You can do that with the fixed-address option.
My phone receives a lease from the DHCP pool, which is 10.42.200.1 to 10.42.200.250 (just realized .50 would be large enough, but not intervening in any way) .
I could try to give my phone a lease in the 10.42.60.x range too just to test it. But if that solves it, something weird is going on.